Method and composition for treating sarcopenia

ABSTRACT

A method of treating sarcopenia comprises immunizing a subject in need thereof against AGE-modified proteins or peptides of a cell. Immunizing a subject includes administering a vaccine that comprises an AGE antigen. Vaccines against AGE-modified proteins or peptides contain an AGE antigen, an adjuvant, optional preservatives and optional excipients.

BACKGROUND

Sarcopenia is the loss of muscle mass, quality and strength associated with aging. Humans begin to lose muscle mass and function at some point in the third decade of life. This loss of muscle mass typically accelerates around age 75. Sarcopenia develops in both physically active and physically inactive people. As the average human lifespan continues to increase, sarcopenia is becoming a significant health concern. The loss of muscle mass from sarcopenia may lead to poor balance, reduced gait speed and frailty. Individuals suffering from sarcopenia are more susceptible to injury and disability, and may be unable to live independently as a result. The spread of sarcopenia will likely result in increases in health care and assisted living expenses.

Sarcopenia has been considered to be an inevitable result of aging and the natural deterioration of the body over time. The primary treatment for sarcopenia is exercise. Physical exercise, particularly resistance training or strength training, can reduce the impact of sarcopenia. Testosterone, anabolic steroids, ghrelin, vitamin D, angiotensin converting enzyme inhibitors (ACE inhibitors), eicosapentaenoic acid (EPA), myostatin, selective androgen receptor modulators (SARMs), urocortin II (Ucn2) and hormone replacement therapy have been investigated or are being studied as potential treatments for sarcopenia. Despite this research, there are currently no U.S. Food and Drug Administration (FDA)-approved agents for treating sarcopenia.

A recent study has identified a causal link between cellular senescence and age-related disorders, such as sarcopenia. A research team at the Mayo Clinic in Rochester, Minn., demonstrated that effects of aging in mice could be delayed by eliminating senescent cells in their fat and muscle tissues without overt side effects (Baker, D. J. et al., “Clearance of p16^(Ink4a)-positive senescent cells delays aging-associated disorders”, Nature, Vol. 479, pp. 232-236, (2011)). Elimination of senescent cells in transgenic mice was shown to substantially delay the onset of sarcopenia and cataracts, and to reduce senescence indicators in skeletal muscle and the eye. The study established that life-long and late-life treatment of transgenic mice for removal of senescent cells has no negative side effects and selectively delays age-related phenotypes that depend on cells (Id., page 234, col. 2, line 16 through page 235, col. 1, line 2). The authors theorized that removal of senescent cells may represent an avenue for treating or delaying age-related diseases in humans and improving healthy human lifespan (Id., page 235, col. 2, lines 38-51).

Senescent cells are cells that are partially-functional or non-functional and are in a state of irreversible proliferative arrest. Senescence is a distinct state of a cell, and is associated with biomarkers, such as activation of the biomarker p16^(Ink4a), and expression of β-galactosidase.

Advanced glycation end-products (also referred to as AGEs, AGE-modified proteins or peptides, or glycation end-products) are known to develop in aging cells and have been identified as a marker for cellular senescence. See, for example, International Application Pub. No. WO 2009/143411 to Gruber (26 Nov. 2009). The non-enzymatic reaction of sugars with protein or peptide side-chains produces AGEs. The formation of AGEs begins with a reversible reaction between a reducing sugar and an amino group to form a Schiff base, which proceeds to form a covalently-bonded Amadori product. Once formed, the Amadori product undergoes further rearrangement to produce AGEs. Hyperglycemia and oxidative stress promote this post--translational modification of membrane proteins or peptides. AGEs have been associated with several pathological conditions including diabetic complications, inflammation, retinopathy, nephropathy, atherosclerosis, stroke, endothelial cell dysfunction and neurodegenerative disorders.

Vaccines have been widely used since their introduction by Edward Jenner in the 1770s to confer immunity against a wide range of diseases and afflictions. Vaccine preparations contain a selected immunogenic agent capable of stimulating immunity to an antigen. Typically, antigens are used as the immunogenic agent in vaccines, such as, for example, viruses, either killed or attenuated, and purified viral components. Antigens used in the production of cancer vaccines include, for example, tumor-associated carbohydrate antigens (TACAs), dendritic cells, whole cells and viral vectors. Different techniques are employed to produce the desired amount and type of antigen being sought. For example, pathogenic viruses are grown either in eggs or cells. Recombinant DNA technology is often utilized to generate attenuated viruses for vaccines.

Immunity is a long-term immune response, either cellular or humoral. A cellular immune response is activated when an antigen is presented, preferably with a co-stimulator to a T-cell which causes it to differentiate and produce cytokines. The cells involved in the generation of the cellular immune response are two classes of T-helper (Th) cells, Th1 and Th2. Th1 cells stimulate B cells to produce predominantly antibodies of the IgG2A isotype, which activates the complement cascade and binds the Fc receptors of macrophages, while Th2 cells stimulate B cells to produce IgG1 isotype antibodies in mice, IgG4 isotype antibodies in humans, and IgE isotype antibodies. The human body also contains “professional” antigen-presenting cells such as dendritic cells, macrophages, and B cells.

A humoral immune response is triggered when a B cell selectively binds to an antigen and begins to proliferate, leading to the production of a clonal population of cells that produce antibodies that specifically recognize that antigen and which may differentiate into antibody-secreting cells, referred to as plasma-cells or memory-B cells. Antibodies are molecules produced by B-cells that bind a specific antigen. The antigen-antibody complex triggers several responses, either cell-mediated, for example by natural killers (NK) or macrophages, or serum-mediated, for example by activating the complement system, a complex of several serum proteins that act sequentially in a cascade that result in the lysis of the target cell.

Immunological adjuvants (also referred to simply as “adjuvants”) are the component(s) of a vaccine which augment the immune response to the immunogenic agent. Adjuvants function by attracting macrophages to the immunogenic agent and then presenting the agent to the regional lymph nodes to initiate an effective antigenic response. Adjuvants may also act as carriers themselves for the immunogenic agent. Adjuvants may induce an inflammatory response, which may play an important role in initiating the immune response. Adjuvants include mineral compounds such as aluminum salts, oil emulsions, bacterial products, liposomes, immunostimulating complexes and squalene.

Other components of vaccines include pharmaceutically acceptable excipients, preservatives, diluents and pH adjusters. A variety of these components of vaccines, as well as adjuvants, are described in www.cdc.gov/vaccines/pubs/pinkbook/downloads/appendices/B/excipient-table-2.pdf and Vogel, F. R. et al., “A compendium of vaccine adjuvants and excipients”, Pharmaceutical Biotechnology, Vol. 6, pp. 141-228 (1995).

Vaccines may therefore be used to stimulate the production of antibodies in the body and provide immunity against antigens. When an antigen is introduced to a subject that has been vaccinated and developed immunity to that antigen, the immune system may destroy or remove cells that express the antigen.

SUMMARY

In a first aspect, the invention is a method of treating sarcopenia comprising immunizing a subject in need thereof against AGE-modified proteins or peptides of a cell.

In a second aspect, the invention is a method of treating a subject with sarcopenia comprising administering a first vaccine comprising a first AGE antigen and administering a second vaccine comprising a second AGE antigen. The second AGE antigen is different from the first AGE antigen.

In a third aspect, the invention is a method of treating a subject with sarcopenia comprising a first administering of a vaccine comprising an AGE antigen, followed by testing the subject for AGE antibody production, followed by a second administering of the vaccine comprising the AGE antigen.

In a fourth aspect, the invention is use of an AGE antigen for the manufacture of a medicament for treating sarcopenia.

In a fifth aspect, the invention is a composition comprising AGE antigens for use in treating sarcopenia.

In a sixth aspect, the invention is a vaccine comprising (a) a first AGE antigen, (b) a second AGE antigen, (c) an adjuvant, (d) optionally, a preservative, and (e) optionally, an excipient. The first AGE antigen is different from the second AGE antigen.

In a seventh aspect, the invention is a method of treating a human subject comprising immunizing the subject against AGE-modified proteins or peptides of a cell. The subject is at least 25 years of age, the subject's muscle mass is two standard deviations or more below the mean value for healthy 25 year olds of the same gender, the subject's muscle function is two standard deviations or more below the mean value for healthy 25 year olds of the same gender and no alternative pathology has been identified to account for the reduced muscle mass and reduced muscle function.

In an eighth aspect, the invention is a method of preventing or delaying the onset of cataracts comprising immunizing a subject in need thereof against AGE-modified proteins or peptides of a cell.

In a ninth aspect, the invention is a method of preventing or delaying the onset of loss of adipose tissue comprising immunizing a subject in need thereof against AGE-modified proteins or peptides of a cell.

In a tenth aspect, the invention is a method of preventing or delaying the onset of lordokyphosis comprising immunizing a subject in need thereof against AGE-modified proteins or peptides of a cell.

In an eleventh aspect, the invention is a method of increasing health span comprising administering a vaccine comprising an AGE antigen.

DEFINITIONS

The term “sarcopenia” means the syndrome characterized by the presence of (1) low muscle mass and (2) low muscle function (low muscle strength or reduced physical performance). Muscle mass may be measured by body imaging techniques, such as computed tomography scanning (CT scan), magnetic resonance imaging (MRI) or dual energy X-ray absorptiometry (DXA or DEXA); bioimpedance analysis (BIA); body potassium measurement, such as total body potassium (TBK) or partial body potassium (PBK); or anthropometric measurements, such as mid-upper arm circumference, skin fold thickness or calf circumference. Preferably, muscle mass is measured by CT scan, MRI or DXA. Muscle strength may be measured by handgrip strength, knee flexion/extension or peak expiratory flow. Preferably, muscle strength is measured by handgrip strength. Physical performance may be measured by the Short Physical Performance Battery, gait speed measurement, timed get-up-and-go (TGUG) or the stair climb power test. Preferably, physical performance is measured by gait speed measurement. A subject may be identified as having sarcopenia or in need of treatment if (1) the subject is at least 25 years old and (2) his or her measured muscle mass and measured muscle function are two standard deviations or more below the mean value for healthy 25 year olds of the same gender and no alternative pathology has been identified to account for the reduced muscle mass and reduced muscle function. Preferably, a subject being treated for sarcopenia is at least 40 years old. More preferably, a subject being treated for sarcopenia is at least 50 years old. Most preferably, a subject being treated for sarcopenia is at least 60 years old. Alternatively, a subject may be identified as having sarcopenia or in need of treatment if (1) his or her gait speed is less than 1.0 m/s across a 4 m course and (2) he or she has an objectively measured low muscle mass, such as, for example, an appendicular mass relative to the square of height less than or equal to 7.23 kg/m² for male subjects or less than or equal to 5.67 kg/m² for female subjects (Fielding, R. A., et al., “Sarcopenia: an undiagnosed condition in older adults. Current consensus definition: prevalence, etiology, and consequences”, Journal of the American Medical Directors Association, Vol. 12(4), pp. 249-256 (May 2011).

The terms “advanced glycation end-product,” “AGE,” “AGE-modified protein or peptide,” and “glycation end-product” refer to modified proteins or peptides that are formed as the result of the reaction of sugars with protein side chains that further rearrange and form irreversible cross-links. This process begins with a reversible reaction between a reducing sugar and an amino group to form a Schiff base, which proceeds to form a covalently-bonded Amadori rearrangement product. Once formed, the Amadori product undergoes further rearrangement to produce AGEs. AGE-modified proteins and antibodies to AGE-modified proteins are described in U.S. 5,702,704 to Bucala (“Bucala”) and U.S. 6,380,165 to Al-Abed et al. (“Al-Abed”). Glycated proteins or peptides that have not undergone the necessary rearrangement to form AGEs, such as N-deoxyfructosyllysine found on glycated albumin, are not AGEs. AGEs may be identified by the presence of AGE modifications (also referred to as AGE epitopes or AGE moieties) such as 2-(2-furoyl)-4(5)-(2-furanyl)-1H-imidazole (“FFI”); 5-hydroxymethyl-1-alkylpyrrole-2-carbaldehyde (“Pyrraline”); 1-alkyl-2-formyl-3,4-diglycosyl pyrrole (“AFGP”), a non-fluorescent model AGE; carboxymethyllysine; and pentosidine. ALI, another AGE, is described in Al-Abed.

The term “AGE antigen” means a substance that elicits an immune response against an AGE-modified protein or peptide of a cell. The immune response against an AGE-modified protein or peptide of a cell does not include the production of antibodies to the non-AGE-modified protein or peptide.

The term “AGE antibody” means an antibody specific for an AGE-modified protein or peptide of a cell.

The term “senescent cell” means a cell which is in a state of irreversible proliferative arrest and expresses one or more biomarkers of senescence, such as activation of p16^(Ink4a) or expression of β-galactosidase. Also included are cells which express one or more biomarkers of senescence, do not proliferate in vivo, but may proliferate in vitro under certain conditions, such as some satellite cells found in the muscles of ALS patients.

The term “increasing health span” means reducing age-related phenotypes. Age-related phenotypes include, for example, sarcopenia, cataracts, loss of adipose tissue and lordokyphosis.

DETAILED DESCRIPTION

The identification of a link between cellular senescence and sarcopenia allows for new treatment possibilities. For example, if the immunogenic agent of a vaccine is an AGE-modified protein or peptide, the immune system of an immunized subject may kill or induce apoptosis in cells expressing the AGE-modified protein or peptide.

The present invention makes use of the discovery that enhanced clearance of cells expressing AGE-modified proteins or peptides (AGE-modified cells) is beneficial in treating or ameliorating sarcopenia. Vaccination against AGE-modified proteins or peptides of a cell produces the desired result of controlling the presence of AGE-modified cells in a subject in need thereof. The continuous and virtually ubiquitous surveillance exercised by the immune system in the body in response to a vaccination allows maintaining low levels of AGE-modified cells in the body. Vaccination against AGE-modified proteins or peptides of a cell can help remove or kill senescent cells. The process of senescent cell removal or destruction allows vaccination against AGE-modified proteins or peptides of a cell to be used to treat sarcopenia.

Vaccination against AGE-modified proteins or peptides of a cell may also be used for increasing health span. Health span may be increased by reducing age-related phenotypes. The vaccine may be used, for example, to prevent or delay the onset of cataracts, lordokyphosis or loss of adipose tissue.

Vaccines against AGE-modified proteins or peptides contain an AGE antigen, an adjuvant, optional preservatives and optional excipients. Examples of AGE antigens include AGE-modified proteins or peptides such as AGE-antithrombin III, AGE-calmodulin, AGE-insulin, AGE-ceruloplasmin, AGE-collagen, AGE-cathepsin B, AGE-albumin, AGE-crystallin, AGE-plasminogen activator, AGE-endothelial plasma membrane protein, AGE-aldehyde reductase, AGE-transferrin, AGE-fibrin, AGE-copper/zinc SOD, AGE-apo B, AGE-fibronectin, AGE-pancreatic ribose, AGE-apo A-I and II, AGE-hemoglobin, AGE-Na⁺/K⁺-ATPase, AGE-plasminogen, AGE-myelin, AGE-lysozyme, AGE-immunoglobulin, AGE-red cell Glu transport protein, AGE-β-N-acetyl hexominase, AGE-apo E, AGE-red cell membrane protein, AGE-aldose reductase, AGE-ferritin, AGE-red cell spectrin, AGE-alcohol dehydrogenase, AGE-haptoglobin, AGE-tubulin, AGE-thyroid hormone, AGE-fibrinogen, AGE-β₂-microglobulin, AGE-sorbitol dehydrogenase, AGE-α₁-antitrypsin, AGE-carbonate dehydratase, AGE-RNAse, AGE-low density lipoprotein, AGE-hexokinase, AGE-apo C-I, AGE-RNAse, AGE-hemoglobin such as AGE-human hemoglobin, AGE-albumin such as AGE-bovine serum albumin (AGE-BSA) and AGE-human serum albumin, AGE-low density lipoprotein (AGE-LDL) and AGE-collagen IV. AGE-modified cells, such as AGE-modified erythrocytes, whole, lysed, or partially digested, may also be used as AGE antigens. Suitable AGE antigens also include proteins or peptides that exhibit AGE modifications (also referred to as AGE epitopes or AGE moieties) such as carboxymethyllysine, carboxyethyllysine, pentosidine, pyrraline, FFI, AFGP and ALI. Further details of some of these AGE-modified proteins or peptides and their preparation are described in Bucala.

A particularly preferred AGE antigen is a protein or peptide that exhibits a carboxymethyllysine AGE modification. Carboxymethyllysine (also known as CML, N(epsilon)-(carboxymethyl)lysine, N(6)-carboxymethyllysine, or 2-Amino-6-(carboxymethylamino)hexanoic acid) is found on proteins or peptides and lipids as a result of oxidative stress and chemical glycation, and has been correlated with aging. CML-modified proteins or peptides are recognized by the receptor RAGE which is expressed on a variety of cells. CML has been well-studied and CML-related products are commercially available. For example, Cell Biolabs, Inc. sells CML-BSA antigens, CML polyclonal antibodies, CML immunoblot kits, and CML competitive ELISA kits (www.cellbiolabs.com/cml-assays).

AGE antigens may be conjugated to carrier proteins to enhance antibody production in a subject. Antigens that are not sufficiently immunogenic alone may require a suitable carrier protein to stimulate a response from the immune system. Examples of suitable carrier proteins include keyhole limpet hemocyanin (KLH), serum albumin, bovine thyroglobulin, cholera toxin, labile enterotoxin, silica particles and soybean trypsin inhibitor. Preferably, the carrier protein is KLH. KLH has been extensively studied and has been identified as an effective carrier protein in experimental cancer vaccines. A preferred AGE antigen-carrier protein conjugate is CML-KLH.

Adjuvants include mineral compounds such as aluminum salts, oil emulsions, bacterial products, liposomes, immunostimulating complexes and squalene. Aluminum compounds are the most widely used adjuvants in human and veterinary vaccines. These aluminum compounds include aluminum salts such as aluminum phosphate (AIPO₄) and aluminum hydroxide (Al(OH)₃) compounds, typically in the form of gels, and are generically referred to in the field of vaccine immunological adjuvants as “alum.” Aluminum hydroxide is a poorly crystalline aluminum oxyhydroxide having the structure of the mineral boehmite. Aluminum phosphate is an amorphous aluminum hydroxyphosphate. Negatively charged species (for example, negatively charged antigens) can absorb onto aluminum hydroxide gels at neutral pH, whereas positively charged species (for example, positively charged antigens) can absorb onto aluminum phosphate gels at neutral pH. It is believed that these aluminum compounds provide a depot of antigen at the site of administration, thereby providing a gradual and continuous release of antigen to stimulate antibody production. Aluminum compounds tend to more effectively stimulate a cellular response mediated by Th2, rather than Th1 cells.

Emulsion adjuvants include water-in-oil emulsions (for example, Freund's adjuvants, such as killed mycobacteria in oil emulsion) and oil-in-water emulsions (for example, MF-59). Emulsion adjuvants include an immunogenic component, for example squalene (MF-59) or mannide oleate (Incomplete Freund's Adjuvants), which can induce an elevated humoral response, increased T cell proliferation, cytotoxic lymphocytes and cell-mediated immunity.

Liposomal or vesicular adjuvants (including paucilamellar lipid vesicles) have lipophilic bilayer domains and an aqueous milieu which can be used to encapsulate and transport a variety of materials, for example an antigen. Paucilamellar vesicles (for example, those described in U.S. Pat. No. 6,387,373) can be prepared by mixing, under high pressure or shear conditions, a lipid phase comprising a non-phospholipid material (for example, an amphiphile surfactant; see U.S. Pat. Nos. 4,217,344; 4,917,951; and 4,911,928), optionally a sterol, and any water-immiscible oily material to be encapsulated in the vesicles (for example, an oil such as squalene oil and an oil-soluble or oil-suspended antigen); and an aqueous phase such as water, saline, buffer or any other aqueous solution used to hydrate the lipids. Liposomal or vesicular adjuvants are believed to promote contact of the antigen with immune cells, for example by fusion of the vesicle to the immune cell membrane, and preferentially stimulate the Th1 sub-population of T-helper cells.

Other types of adjuvants include Mycobacterium bovis bacillus Calmette-Guérin (BCG), quill-saponin and unmethylated CpG dinucleotides (CpG motifs). Additional adjuvants are described in U.S. Patent Application Publication Pub. No. US 2010/0226932 (Sep. 9, 2010) and Jiang, Z-H. et al. “Synthetic vaccines: the role of adjuvants in immune targeting”, Current Medicinal Chemistry, Vol. 10(15), pp. 1423-39 (2003). Preferable adjuvants include Freund's complete adjuvant and Freund's incomplete adjuvant.

The vaccine may optionally include one or more preservatives, such as antioxidants, antibacterial and antimicrobial agents, as well as combinations thereof. Examples include benzethonium chloride, ethylenediamine-tetraacetic acid sodium (EDTA), thimerosal, phenol, 2-phenoxyethanol, formaldehyde and formalin; antibacterial agents such as amphotericin B, chlortetracycline, gentamicin, neomycin, polymyxin B and streptomycin; antimicrobial surfactants such as polyoxyethylene-9, 10-nonyl phenol (Triton N-101, octoxynol-9), sodium deoxycholate and polyoxyethylated octyl phenol (Triton X-I00). The production and packaging of the vaccine may eliminate the need for a preservative. For example, a vaccine that has been sterilized and stored in a sealed container may not require a preservative.

Other components of vaccines include pharmaceutically acceptable excipients, such as stabilizers, thickening agents, toxin detoxifiers, diluents, pH adjusters, tonicity adjustors, surfactants, antifoaming agents, protein stabilizers, dyes and solvents. Examples of such excipients include hydrochloric acid, phosphate buffers, sodium acetate, sodium bicarbonate, sodium borate, sodium citrate, sodium hydroxide, potassium chloride, potassium chloride, sodium chloride, polydimethylsilozone, brilliant green, phenol red (phenolsulfon-phthalein), glycine, glycerin, sorbitol, histidine, monosodium glutamate, potassium glutamate, sucrose, urea, lactose, gelatin, sorbitol, polysorbate 20, polysorbate 80 and glutaraldehyde.

The vaccine may be provided in unit dosage form or in multidosage form, such as 2-100 or 2-10 doses. The unit dosages may be provided in a vial with a septum, or in a syringe with or without a needle. The vaccine may be administered intravenously, subdermally or intraperitoneally. Preferably, the vaccine is sterile.

The vaccine may be administered one or more times, such as 1 to 10 times, including 2, 3, 4, 5, 6, 7, 8 or 9 times, and may be administered over a period of time ranging from 1 week to 1 year, 2-10 weeks or 2-10 months. Furthermore, booster vaccinations may be desirable, over the course of 1 year to 20 years, including 2, 5, 10 and 15 years.

A subject that receives a vaccine for AGE-modified proteins or peptides of a cell may be tested to determine if he or she has developed an immunity to the AGE-modified proteins or peptides. Suitable tests may include blood tests for detecting the presence of an antibody, such as immunoassays or antibody titers. Alternatively, an immunity to AGE-modified proteins or peptides may be determined by measuring changes in muscle mass over time. For example, a baseline muscle mass in a subject may be measured followed by administration of the vaccine for AGE-modified proteins or peptides of a cell. Immunity to AGE-modified proteins or peptides may be determined by periodically measuring muscle mass in the subject and comparing the subsequent measurements to the baseline measurement. A subject may be considered to have developed an immunity to AGE-modified proteins or peptides if he or she does not demonstrate loss of muscle mass between subsequent measurements or over time. Alternatively, the concentration and/or number of senescent cells in fat or muscle tissue may also be monitored. Vaccination and subsequent testing may be repeated until the desired therapeutic result is achieved.

The vaccination process may be designed to provide immunity against multiple AGE moieties. A single AGE antigen may induce the production of AGE antibodies which are capable of binding to multiple AGE moieties. Alternatively, the vaccine may contain multiple AGE antigens. In addition, a subject may receive multiple vaccines, where each vaccine contains a different AGE antigen.

Any mammal that could develop sarcopenia may be treated by the methods herein described. Humans are a preferred mammal for treatment. Other mammals that may be treated include mice, rats, goats, sheep, cows, horses and companion animals, such as dogs or cats. A subject in need of treatment may be identified by the diagnosis of a disease or disorder that is known to cause elevated levels of AGEs such as, for example, diabetes mellitus (both Type 1 and Type 2), or the presence of a pathological condition associated with AGEs such as, for example, atherosclerosis, inflammation, retinopathy, nephropathy, stroke, endothelial cell dysfunction or neurodegenerative disorders. In addition, subjects may be identified for treatment based on their age. For example, a human over 75 years of age may be vaccinated with an AGE antigen to treat sarcopenia, while a human under 30 years of age might not be identified as in need of vaccination. Alternatively, any of the mammals or subjects identified above may be excluded from the patient population in need of vaccination.

A human subject may be identified as having sarcopenia or in need of treatment if (1) the subject is at least 25 years old and (2) his or her measured muscle mass and measured muscle function are two standard deviations or more below the mean value for healthy 25 year olds of the same gender and no alternative pathology has been identified to account for the reduced muscle mass and reduced muscle function. Preferably, a subject being treated for sarcopenia is at least 40 years old. More preferably, a subject being treated for sarcopenia is at least 50 years old. Most preferably, a subject being treated for sarcopenia is at least 60 years old. Alternatively, a subject may be identified as having sarcopenia or in need of treatment if (1) his or her gait speed is less than 1.0 m/s across a 4 m course and (2) he or she has an objectively measured low muscle mass, such as, for example, an appendicular mass relative to the square of height less than or equal to 7.23 kg/m² for male subjects or less than or equal to 5.67 kg/m² for female subjects.

EXAMPLES Example 1 (Prophetic) An AGE-RNAse Containing Vaccine in a Human Subject

AGE-RNAse is prepared by incubating RNAse in a phosphate buffer solution containing 0.1-3 M glucose, glucose-6-phosphate, fructose or ribose for 10-100 days. The AGE-RNAse solution is dialyzed and the protein content is measured. Aluminum hydroxide or aluminum phosphate, as an adjuvant, is added to 100 μg of the AGE-RNAse. Formaldehyde or formalin is added as a preservative to the preparation. Ascorbic acid is added as an antioxidant. The vaccine also includes phosphate buffer to adjust the pH and glycine as a protein stabilizer.

The composition is injected into a human subject subcutaneously. The subject's muscle mass is measured at the time of injection to establish a baseline muscle mass value. The patient's muscle mass is measured again after one month. The one-month muscle mass value is compared to the baseline value. Additional injections are performed and additional muscle mass measurements are taken every month until the muscle mass measurement indicates no change, or an increase, from the baseline value.

Example 2 (Prophetic) Injection Regimen for an AGE-RNAse Containing Vaccine in a Human Subject

The same vaccine as described in Example 1 is injected into a human subject. The titer of antibodies to AGE-RNAse is determined by ELISA after two weeks. Additional injections are performed after three weeks and six weeks, respectively. Further titer determination is performed two weeks after each injection.

Example 3 (Prophetic) An AGE-Hemoglobin Containing Vaccine in a Human Subject

AGE-hemoglobin is prepared by incubating human hemoglobin in a phosphate buffer solution containing 0.1-3 M glucose, glucose-6-phosphate, fructose or ribose for 10-100 days. The AGE-hemoglobin solution is dialyzed and the protein content is measured. All vaccine components are the same as in Example 1, except AGE-hemoglobin is substituted for AGE-RNAse.

Administration is carried out as in Example 1, or as in Example 2. The number of senescent cells in the subject's adipose tissue is measured at the time of injection to establish a baseline number of senescent cells. The number of senescent cells in the subject's adipose tissue is measured again two months after injection and is compared to the baseline number of senescent cells. Additional injections are performed and additional senescent cell measurements are taken every two months to determine if the number of senescent cells in adipose tissue is increasing or decreasing, or if there is no change in the number of senescent cells in adipose tissue.

Example 4 (Prophetic) An AGE-Human Serum Albumin Containing Vaccine in a Human Subject

AGE-human serum albumin is prepared by incubating human serum albumin in a phosphate buffer solution containing 0.1-3 M glucose, glucose-6-phosphate, fructose or ribose for 10-100 days. The AGE-human serum albumin solution is dialyzed and the protein content is measured. All vaccine components are the same as in Example 1, except AGE-human serum albumin is substituted for AGE-RNAse. Administration is carried out as in Example 1, or as in Example 2.

Example 5 In Vivo Study of the Administration of Anti-AGE Antibody

To examine the effects of an anti-AGE antibody, the antibody was administered to the aged CD1(ICR) mouse (Charles River Laboratories), twice daily by intravenous injection, once a week, for three weeks (Days 1, 8 and 15), followed by a 10 week treatment-free period. The test antibody was a commercially available mouse anti-AGE antibody raised against carboxymethyl lysine conjugated with keyhole limpet hemocyanin. A control reference of physiological saline was used in the control animals.

Mice referred to as “young” were 8 weeks old, while mice referred to as “old” were 88 weeks (±2 days) old. No adverse events were noted from the administration of the antibody. The different groups of animals used in the study are shown in Table 1.

TABLE 1 Number of Animals Dose Level Main Treatment- Group Test (μg/gm/ Study Free No. Material Mice BID/week) Females Females 1 Saline young 0 20 — 2 Saline old 0 20 20 3 Antibody old 2.5 20 20 4 None old 0 20 pre 5 Antibody old 5.0 20 20 — = Not Applicable, Pre = Subset of animals euthanized prior to treatment start for collection of adipose tissue.

p16^(INK4a) mRNA, a marker for senescent cells, was quantified in adipose tissue of the groups by Real Time-qPCR. The results are shown in Table 2. In the table ΔΔCt=ΔCt mean control Group (2)−ΔCt mean experimental Group (1 or 3 or 5); Fold Expression=2^(−ΔΔCt).

TABLE 2 Calculation Group 2 Group 2 Group 2 (unadjusted to vs Group 1 vs Group 3 vs Group 5 Group 4: 5.59) Group 2 Group 1 Group 2 Group 3 Group 2 Group 5 Mean ΔCt 5.79 7.14 5.79 6.09 5.79 7.39 ΔΔCt −1.35 −0.30 −1.60 Fold Expression 2.55 1.23 3.03

The table above indicates that untreated old mice (Control Group 2) express 2.55-fold more p16^(Ink4a) mRNA than the untreated young mice (Control Group 1), as expected. This was observed when comparing Group 2 untreated old mice euthanized at end of recovery Day 85 to Group 1 untreated young mice euthanized at end of treatment Day 22. When results from Group 2 untreated old mice were compared to results from Group 3 treated old mice euthanized Day 85, it was observed that p16^(Ink4a) mRNA was 1.23-fold higher in Group 2 than in Group 3. Therefore, the level of p16^(Ink4a) mRNA expression was lower when the old mice were treated with 2.5 pg/gram/BID/week of antibody.

When results from Group 2 (Control) untreated old mice were compared to results from Group 5 (5 μg/gram) treated old mice euthanized Day 22, it was observed that p16^(Ink4a) mRNA was 3.03-fold higher in Group 2 (controls) than in Group 5 (5 pg/gram). This comparison indicated that the Group 5 animals had lower levels of p16^(Ink4a) mRNA expression when they were treated with 5.0 μg/gram/BID/week, providing p16^(Ink4a) mRNA expression levels comparable to that of the young untreated mice (Group 1). Unlike Group 3 (2.5 μg/gram) mice that were euthanized at end of recovery Day 85, Group 5 mice were euthanized at end of treatment Day 22.

These results indicate the antibody administration resulted in the killing of senescent cells.

The mass of the gastrocnemius muscle was also measured, to determine the effect of antibody administration on a classic sign of aging, sarcopenia. The results are shown in Table 3. The results indicate that administration of the antibody increased muscle mass as compared to controls, but only at the higher dosage of 5.0 μg/gm/BID/week.

TABLE 3 Weight relative to Summary Absolute weight of body mass of Group Information Gastrocnemius Muscle Gastrocnemius Muscle 1 Mean 0.3291 1.1037 SD 0.0412 0.1473 N 20 20 2 Mean 0.3304 0.7671 SD 0.0371 0.1246 N 20 20 3 Mean 0.3410 0.7706 SD 0.0439 0.0971 N 19 19 5 Mean 0.4074 0.9480 SD 0.0508 0.2049 N 9 9

These results demonstrate that administration of antibodies that bind to AGEs of a cell resulted in a reduction of cells expressing p16^(Ink4a), a biomarker of senescence. The data show that reducing senescent cells leads directly to an increase in muscle mass in aged mice. These results indicate that the loss of muscle mass, a classic sign of sarcopenia, can be treated by administration of antibodies that bind to AGEs of a cell.

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What is claimed is:
 1. A method of treating sarcopenia, comprising immunizing a subject in need thereof against AGE-modified proteins or peptides of a cell.
 2. The method of claim 1, wherein the immunizing comprises administering a vaccine comprising an AGE antigen.
 3. The method of claim 2, wherein the vaccine comprises (a) the AGE antigen, (b) an adjuvant, (c) optionally, a preservative, and (d) optionally, an excipient.
 4. The method of claim 1, wherein the subject is selected from the group consisting of humans, mice, rats, goats, sheep, cows, horses, dogs and cats.
 5. The method of claim 4, wherein the subject is a human.
 6. The method of claim 2, wherein the vaccine is administered in an amount effective to cause the immune system to produce antibodies to cells expressing AGE-modified proteins or peptides.
 7. The method of claim 1, wherein the subject does not have type 2 diabetes.
 8. The method of claim 1, wherein the subject does not have diabetes.
 9. The method of claim 2, wherein the AGE antigen is an AGE-modified protein or peptide selected from the group consisting of AGE-RNAse, AGE-human hemoglobin, AGE-human serum albumin, AGE-low density lipoprotein, AGE-collagen IV, AGE-antithrombin III, AGE-calmodulin, AGE-insulin, AGE-ceruloplasmin, AGE-collagen, AGE-cathepsin B, AGE-albumin, AGE-crystallin, AGE-plasminogen activator, AGE-endothelial plasma membrane protein, AGE-aldehyde reductase, AGE-transferrin, AGE-fibrin, AGE-copper/zinc SOD, AGE-apo B, AGE-fibronectin, AGE-pancreatic ribose, AGE-apo A-I and II, AGE-hemoglobin, AGE-Na⁺/K⁺-ATPase, AGE-plasminogen, AGE-myelin, AGE-lysozyme, AGE-immunoglobulin, AGE-red cell Glu transport protein, AGE-β-N-acetyl hexominase, AGE-apo E, AGE-red cell membrane protein, AGE-aldose reductase, AGE-ferritin, AGE-red cell spectrin, AGE-alcohol dehydrogenase, AGE-haptoglobin, AGE-tubulin, AGE-thyroid hormone, AGE-fibrinogen, AGE-β₂-microglobulin, AGE-sorbitol dehydrogenase, AGE-α₁-antitrypsin, AGE-carbonate dehydratase, AGE-RNAse, AGE-low density lipoprotein, AGE-hexokinase, AGE-apo C-I, and mixtures thereof.
 10. The method of claim 2, wherein the AGE antigen comprises at least one protein or peptide that exhibits AGE modifications selected from the group consisting of carboxymethyllysine, carboxyethyllysine, pentosidine, pyrraline, IFFI, AFGP, and ALI.
 11. The method of claim 2, wherein the AGE antigen comprises a carboxymethyllysine-modified protein or peptide.
 12. The method of claim 2, wherein the vaccine is sterile, and the vaccine is in unit dosage form.
 13. The method of claim 2, wherein the vaccine is sterile, and the vaccine is in multidosage form.
 14. A method of treating a subject with sarcopenia, comprising: administering a first vaccine comprising a first AGE antigen; and administering a second vaccine comprising a second AGE antigen; wherein the second AGE antigen is different from the first AGE antigen.
 15. The method of claim 14, further comprising administering additional vaccines comprising additional AGE antigens, wherein the AGE antigen in each vaccine is different.
 16. The method of claim 14, wherein the first AGE antigen comprises a carboxymethyllysine-modified protein or peptide.
 17. The method of claim 2, further comprising: testing the subject for AGE antibody production; followed by a second administering of the vaccine comprising the AGE antigen. 18-26. (canceled)
 27. A vaccine, comprising (a) a first AGE antigen, (b) a second AGE antigen, (c) an adjuvant, (d) optionally, a preservative, and (e) optionally, an excipient, wherein the first AGE antigen is different from the second AGE antigen. 28-30. (canceled)
 31. The vaccine of claim 27, wherein the first AGE antigen comprises a carboxymethyl lysine-modified protein or peptide. 32-39. (canceled)
 40. The method of claim 1, wherein the subject has a gait speed less than 1.0 m/s across a 4 m course and an appendicular mass relative to the square of height less than or equal to 7.23 kg/m² for male subjects or less than or equal to 5.67 kg/m² for female subjects. 